In Patent Document 1, for example, a sliding bearing is proposed which includes: a synthetic resin-made cylindrical bearing body; a plurality of first slits provided in the bearing body and extending from one axial end face of the bearing body toward the other axial end face of the bearing body; second slits provided in the bearing body and extending from the other axial end face of the bearing body toward the one axial end face of the bearing body; a sliding surface which is provided on an inner side of the bearing body and partially severed in a direction about an axis by these slits; at least one fitting groove provided in an outer surface of the bearing body; and an elastic ring which is fitted in the fitting groove in such a manner as to partially project radially from the outer surface of the bearing body and to reduce the diameter of the bearing body.